Stacker conveyor with flexible section

ABSTRACT

A stacker conveyor assembly with a flexing section comprised of a stationary truss framework, a movable truss framework pivotally mounted relative to the stationary truss framework for movement in a vertical plane, and a flexible section extending between the stationary and movable truss frameworks for supporting a section of troughed conveyor belt which gently bends through an arc in a vertical plane of the truss frameworks. The ends of the flexible section are connected to the truss frameworks by way of sliding joints which permit longitudinal movement of the flexible section members relative to the truss frameworks, thereby permitting adjustment of the angle of inclination of the movable truss framework.

Unite States Patent Stone et a1.

[ Oct. 15, 1974 [54] STACKER CONVEYOR WITH FLEXlIBLE 2,818,965 1/1958Horth 198 109 SECTION [75] Inventors: Guthrie B. Stone, Honeoye; ArthurPrimary EXamUYerTRChard Schacher Assistant Exammer-Joseph E. ValenzaOrloff, Nunda, Guy J. Wlcksa1l, A A F Cl, A & Fayette, an of NY ttorney,gem, or zrmarence r1611- Harvey B. Jacobson [73] Assignee: StoneConveyor, Inc., Honeoye,

57 ABSTRACT [22] led: 1973 A stacker conveyor assembly with a flexingsection 21] L 337 215 comprised of a stationary truss framework, amovable truss framework pivotally mounted relative to the sta- RelatedApphcatmn Dam tionary truss framework for movement in a vertical 1Continuation of p I971, plane, and a flexible section extending betweenthe abandoned stationary and movable truss frameworks for supporting asection of troughed conveyor belt which gently U-S. bends through an arcin a vertical plane of the truss 1 Clframeworks The ends of the flexiblesection are on. 1581 held of Search 198/1 1, 1091 l l 14, nected to thetruss frameworks by way of sliding joints 198/115, 117, 121, 122, 233;214/10 which permit longitudinal movement of the flexible sectionmembers relative to the truss frameworks, 1 1 References Clted therebypermitting adjustment of the angle of inclina- UNITED STATES PATENTStion of the movable truss framework.

552,716 1/1896 Matthiessen 198/109 2,795,315 6/1957 Hahir et a1 198 1099 Clams l3 Draw'ng guns D oio o l STACKER CONVEYOR WITH FLEXIBLE SECTIONThis is a continuation of application Ser. No. 176,902, filed Sept. 1,197i, now abandoned.

The present invention is generally related to stacker conveyors, and,more particularly, to stacking conveyors used to form storage piles ofmaterials such as gravel, sand, crushed stone, and coal. With many suchmaterials, it is desirable to keep the discharge end of the conveyorclose to the top of the storage pile to minimize the amount of dustgeneration, segregation and degradation of the materials.

Previously, this had been achieved with two types of elevating stackerconveyors. One such conventional stacker conveyor provided means forpivoting the entire conveyor about its loading end to provide verticaladjustment of the discharge end to maintain it in close proximity to thetop of the storage pile. This type of construction, however, was found,for the most part, to be unacceptable for several reasons, one of whichwas the limited overall size and load-carrying capacity. Furthermore,the initial costs of such constructions was unusually high which wascompounded by unusual maintenance and breakdown problems.

Another type of conventional elevating stacker conveyor was providedwith a joint in its mid-section, making it necessary to move only aportion of the entire conveyor in an attempt to alleviate the problemsof the aforementioned construction. Such two-piece conventionalconstructions, however, required that the trough in the conveyor belt beflattened at the joint to permit bending without developing excessivetension in the edge portions of the belt. This greatly limited thecarrying capacity of the belt since the flat section at the joint couldnot carry nearly as much material as the troughed sections of conveyorbelt.

It is an object of the present invention to provide a flexing stackerconveyor assembly having a troughed conveyor belt which is maintained ina troughed condition while passing through a flexing support frame, suchthat the discharge end of the conveyor may be adjusted to the proximityof the storage pile, yet the overall carrying capacity of the conveyoris not significantly reduced.

Another object of the present invention is to provide a stacker conveyorassembly comprised of a movable framework which is pivotally connectedto a stationary conveyor framework with a flexible support frameextending therebetween which bends in a vertical plane to support agently curved section of troughed conveyor belt.

It is a further object of the present invention to provide a versatilestacker conveyor assembly having a flexing framework which gently curvesa section of troughed conveyor belt, such that one end of the conveyormay be moved up and down in the vertical plane to maintain closeproximity to the storage piles of conveyed materials, thus minimizingthe generation of dust, segregation and degradation of the materials.

Still another object of the present invention is to provide a novelflexible section for a stacker conveyor comprised of two pairs ofelongated parallel bending members, the opposite ends of which areslidably connected between a stationary and a movable framework, suchthat the arc of the bending members may be varied to change theinclination of the movable truss framework, permitting the use of atroughed conveyor LII belt along the entire load carrying length of theconveyor assembly.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIG. 1 is an aerial view of a typical storage pile of material formed bythe stacker conveyor assembly of the present invention;

FIG. 2 is a broken elevation of the stacker conveyor assembly in theraised position, with a phantom view of the movable truss framework in alowered position;

FIG. 3 is a partial elevation of the flexing section with the trussframework partially removed;

FIG. 3A is an elevation illustrating the pivotal connection between thestationary and movable truss frameworks;

FIG. 4 is a geometric illustration of the flexing section of the stackerconveyor assembly, with movable framework in the raised and loweredpositions;

FIG. 5 is a plan view of the bending members of the flexing sectionslidably supported between the movable and stationary truss frameworks;

FIG. 5A is a cross-sectional view of the sliding joint connecting thebending members with the truss frameworks;

FIG. 6 is a perspective view of a linkage mounting plate connected tothe tubular members of the flexing station;

FIG. 7 is a perspective view of a flat mounting plate connected to the.tubular members of the flexing section;

FIG. 8 is a cross-sectional view of the flexing members connected to atrough roller support bracket by wayof the flat mounting plate shown inFIG. 7;

FIG. 9 is an end view of the stationary truss framework;

FIG. 10 is an end view of the movable truss framework; and

FIG. 11 is a sectional view of the fixed truss framework taken alongsection 11-11 with a conveyor hood added.

Referring, now, more particularly to FIGS. 1 and 2, the stacker conveyorassembly of the present invention is generally referred to by thenumeral 20, and is adapted to form storage piles 22 of materials such assand, gravel, crushed stone, and coal. The conveyor assembly includes avertical support tower 24 which rests upon a mobile tractor unit 26,which is adapted to be driven or moved along a track or path 28 toprovide an arcuate-shaped storage pile of material. The tractor andvertical support tower may be guided by a pair of horizontal cables 30which are connected at one end to a rotatable rigid base 32 which servesto pivotally accommodate the loading end of the conveyor assembly.

It is appreciated, from the illustration of FIG. 2, that the conveyorassembly is comprised of a movable truss framework 34 which is pivotallymounted for movement between raised and lowered positions, such that thedischarge end of the conveyor may be maintained in close proximity tothe top of the material storage pile. This minimizes the generation ofdust, and the segregation and degradation of the materials beingconveyed to the storage pile. Thus, it can be seen that, not only canthe stacker conveyor assembly of the present invention be articulated ina circular path, but also be raised and lowered to maintain thedischarge end in close proximity to the top of the storage pile. Thisconstruction both minimizes the generation of dust, and

permits the formation of large storage piles of material with a singlestacker conveyor assembly.

A stationary truss framework 36 extends between the pivot support 32 andthe support tower 24 and is approximately one-half the total length ofthe over-all conveyor. A support arm 38 may be provided to stabilize thestationary truss framework relative to the support tower. A fixed guywire 40 extends from the loading end of the stationary truss frameworkto the top area of the vertical support tower 24, and a movable pulleyassembly 42 extends between the top of the supporttower to the movabletruss framework 34 to affect movement between the raised and loweredpositions. Pulley assembly 42 may be driven by conventional motors andwinches not considered to be a part of the present invention and notillustrated in the drawings.

Referring to FIG. 3, a flexing section of the conveyor is generallyreferred to by the numeral 44 and includes a troughed conveyor belt 46made of conventional flexible conveyor belt materials. A plurality ofspaced trough roller assemblies 48 are provided to support the conveyorbelt at points along its length, each assembly being connected to twopairs of tubular members 50 made of steel, or similar materials, andbeing of an elastic quality, such that they are bendable, yet resilientin nature to return to their original straight shape. At least one endof each tubular bending member 50 is journaled in a channel or collar52, of similar crosssectional shape, to form a sliding joint with thestationary and movable truss frameworks respectively to allow forvariation in length during bending, and to keep the ends parallel to theadjacent truss sections. The joints of conventional two-piece stackerconveyor constructions required that the conveyor belt be flattenedwithin the area of the joint. This was required to prevent excessivetension in the outermost edge portions of the belt, due to the acutenessof the angle formed at the joint. With the flexing section of thepresent invention, however. the angle through which the conveyor mustbend is extended, or spread out over a considerable arced length ofconveyor belt. This is due to the length of the bending tubular members50. Such an arrangement greatly reduces the tension in the outermostedge portions of the belt, thereby permitting the belt to be maintainedin its original troughed shape, such that the load capacity of the beltis not reduced as with conventional constructions.

As the troughed conveyor belt moves in the direction of arrow 54, thematerials carried thereby are ultimately unloaded at the end of themovable truss framework, and the belt assumes a flattened condition forreturn in the direction indicated by arrow 56. A plurality of returnidler rollers 58 are provided in the stationary and movable trussframeworks. In addition, the belt travels around a main drive roll orspool 60 driven by a motor in a conventional manner, such that the beltis continuously advanced over the idler rollers and troughed rollerassemblies by which a continuous flow of materials may be achieved.

Main idler rollers 62 and 63 are mounted onto the truss frameworks tofeed and return the conveyor belt to and from a remote idler roller 64connected to a weight box assembly 65, of a conventional type. It isapparent that as the movable truss framework is pivoted toward theraised position, the spacing between main idler roller 62 on movableframework 34 and remote idler roller 64 is slightly increased. At thesame time, the length of conveyor belt traveling over the distance ofthe flexing section is somewhat reduced. Such changes in length arecompensated for by the idler roller 64 and weight box assembly 65 whichmoves vertically to take up any slack in the belt and maintain constantbelt tension. Thus, belt tension is unaffected, regardless of thevertical position of the stacker conveyor assembly.

The connection between the stationary and movable truss frameworks andthe mast is best illustrated in FIG. 3A. It can be seen that a rigidI-beam 66 is welded to the mast to provide a support for a pair ofmounting plates 68 and 69. A pair of pins 70 extend through mountingholes in each plate 68 and 69 and are journaled in collar openings ineach of vthe truss frameworks. As such, the movable truss framework 34is permitted to pivot in a vertical plane about mounting pins 70. Thisarrangement provides a rigid, durable, pivoting joint between the trussframeworks and mast.

It is essential to provide vertical support to the bending tubularmembers 50 to maintain a gently curving arc. A plurality of linkagemembers 72 are provided, each extending between the flexible members 50and a corresponding connecting plate 74. A plurality of inclined linkagemembers 76 extend between the connection plates and the trussframeworks, and the connection plates are interconnected by way of apair of horizontal linkage members 78. Each linkage member is pivotallyfastened to the corresponding connection plate 74 to permit propermovement of the linkage members during corresponding movement of thetruss framework. The geometry of the linkages is such that bendabletubular members 50 are supported by linkages 72 to form a smooth arcthroughout the flexing section. The geometric relationship between thelinkage members and the truss frameworks is best illustrated by FIG. 4.Not only are the bendable tubular members supported by the verticallinkage members, but, also, they are guided to form a gently curved pathwhich is followed by the troughed section of conveyor belt.

Referring to FIG. 5, the slidable mounting arrangement of the flexingsection can be seen in more detail. Each sliding joint assembly 52 iscomprised of an elongated channel 80 which is of a width slightlygreater than the composite width of a corresponding pair of flexibletubular members 50, such that the ends of the tubular members extendinto the channel supports 80, for sliding engagement therewith. In orderto prevent dislodgment of the tubular members during bending, and inorder to provide easy mounting and removal of the tubular members fromthe channel supports 80, a U-shaped mounting bracket 82 is providedwhich fits within the opening of each channel support 80 and is held inposition by a pair of bolts 84.

The geometry of the flexible section 50, the controlling linkage, andthe pivot of the movable truss section is such that there isonly aslight movement of the flexible section in the sliding joint assemblies52, and the position of the flexible section in the sliding jointassemblies is the same at the extreme positions. The distance betweenthe sliding joints measured along the flexible section is a minimum atthe raised and lowered positions of the movable truss section, andincreases slightly at intermediate positions, reaching a maximum nearthe center of travel of the movable truss. This particular geometrypermits the use of sliding joints of minimum length.

Transverse support between the parallel pairs of tubular members isprovided by a plurality of lateral supports 86, the ends of which arewelded to the corresponding tubular members. These weld joints,preferably, are made in the proximity of the attachment of each troughroller assembly 48, as shown in FIG. 8. Each trough roller assembly isheld in position by way of a bolt 88 extending downwardly through thespace separating each pair of tubular members 50 and through a flatmounting plate 90 welded to the tubular members.

FIGS. 6 and 7 illustrate the two types of mounting plates or bracketswhich are welded to the tubular members 50. FIG. 6 shows a linkagemember mounting bracket 92 which is adapted to accept the upper ends ofvertical linkage members 72 shown in FIG. 3, by way of downwardlyextending tab portions 94. Apertures 96 are adapted to accommodate boltswhich fasten the trough roller assemblies to the tubular members in afashion similar to that illustrated in FIG. 8. FIG. 7 shows the flatmounting plate 90 in more detail, the plate being provided with anaperture 96 adapted to accept the bolt arrangement illustrated in FlG.8.

Looking to FIG. 11, it can be seen that the stacker conveyor assembly ofthe present invention may be provided with a hood attachment 100 whichis adapted to cover the troughed conveyor belt to protect the materialagainst the elements. It can also be seen that each trough rollerassembly 48 may be comprised of three rollers, a horizontal roller 102,and a pair of oppositely disposed and oppositely inclined rollers 104and 106 respectively.

FIG. 9 is an end view of the stationary truss framework and illustratesthe relative position of idler rollers 58 and 63. Also, the relativepositions of the sliding joints 52 are shown in more detail. Similarly,FIG. 10 is an end view of the movable truss framework, with the relativepositions of idler rollers 58 and 62 as well as sliding joints 52 beingshown in more detail.

It is apparent from the foregoing description that the stacker conveyorassembly of the present invention provides a means for adjusting thevertical position of the discharge end of the conveyor, yet permittingthe use of a troughed conveyor belt throughout the entire length whichthe material is carried by'the conveyor. This provides for maximumcarrying capacity of the conveyor belt and at the same time requiresmovement of only a portion of the over-all conveyor assembly. Such astacker conveyor assembly is relatively less expensive to producecompared to conventional constructions of comparable load carryingcapacity. Furthermore, the conveyor assembly of the present inventionrequires less framework moving equipment for articulation of the movabletruss framework which not only reduces the initial cost, but also, themaintenance costs over a period of time. Changes in shape or materi alsof the troughed conveyor belt, the troughed roller assemblies or othercomponents of the stacker conveyor assembly are deemed to fall withinthe scope of the present invention.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. A conveyor assembly, said assembly comprising a stationary truss, amovable truss, mounting means pivotally supporting one end of saidmovable truss adjacent a first end of said stationary truss with saidtrusses disposed in closely adjacent end-to-end relation in generallythe same plane and the other end of said movable truss swingable in saidplane, an elongated, stiff but flexible and resilient support structuregenerally paralleling said plane and positioned with its opposite endsoverlapping the adjacent ends of said trusses, first support meanssupporting the opposite ends of said resilient support structure fromremote portions of said trusses spaced therealong from the adjacent endsof said trusses and with said opposite ends generally paralleling thecorresponding truss portions and supported therefrom for limitedlengthwise guided shifting longitudinally therealong, second supportmeans connected to and supported at least in part from said trusses andsupportingly engaged with predetermined portions of said resilientsupport structure disposed at a plurality of points spaced aparttherealong between and from said opposite ends and operative, inresponse to relative angular displacement of said trusses, to supportand automatically shift said spaced predetermined portions of saidsupport structure to predetermined positions along a substantiallyconstant radius path containing the opposite ends of said supportstructure during angular displacement of said movable truss relative tosaid stationary truss, and conveyor belt support means supported fromand closely spaced along said resilient support structure and the remoteend portions of said trusses on the remote sides of said first supportmeans for supporting a flexible conveyor belt in a path substantiallyparalleling the remote end portions of said trusses and said resilientsupport structure in order that the path of that portion of thesupported conveyor belt extending between said remote end portions ofsaid trusses will comprise a substantially constant radius arc whoseopposite ends merge smoothly into the portions of the conveyor beltsupported from said remote end portions.

2. The combination of claim 1 wherein said trusses each include oppositeside longitudinal members, said resilient structure including a pair ofspaced side-byside elongated, stiff but flexible and resilient members,said resilient members each being positioned with their opposite endsoverlapping the adjacent ends of one pair of corresponding sidelongitudinal members and supported therefrom by said first supportmeans.

3. The combination of claim 2 wherein said elongated support structureincludes rigid transverse support members extending between and rigidlyinterconnecting corresponding portions of said resilient memand parallelresilient structural members rigidly interconnected at a plurality ofpoints spaced therealong.

5. The combination of claim 3 wherein said conveyor belt support meansincludes a plurality of belt craddling structures extending between andrigidly connected to said resilient members at points spaced therealong.

6. The combination of claim 1 wherein said trusses each include oppositeside longitudinal members, said resilient support structure including apair of spaced side-by-side elongated, stiff but flexible and resilientmembers, said resilient members each being positioned with theiropposite ends overlapping the adjacent ends of one pair of correspondingside longitudinal members and supported therefrom by said first supportmeans, said first support means comprising a sleeve member supportedfrom and extending along each opposite side longitudinal member, theopposite ends of said resilient members being slidingly telescoped in acorresponding sleeve member.

7. The combination of claim 1 including an upstanding support tower,said first end of said stationary truss being supported from an upperportion of said support tower, said upper portion of said support towercomprising said mounting means for said one end of said movable truss.

8. The combination of claim 7 including means connected between saidtower and the other end of said movable truss for supporting the latterin adjusted angularly displaced positions relative to said stationarytruss.

9. The combination of claim 1 including a stationary base, saidstationary truss being inclined with said first end thereof uppermost,means supporting the second end of said stationary truss from said basefor angular displacement about an upstanding axis, the lower end of saidtower including a mobile support unit adapted to move in an arcuate pathdisposed in a plane normal to said upstanding axis and having the latteras its center of curvature.

1. A conveyor assembly, said assembly comprising a stationary truss, amovable truss, mounting means pivotally supporting one end of saidmovable truss adjacent a first end of said stationary truss with saidtrusses disposed in closely adjacent end-to-end relation in generallythe same plane and the other end of said movable truss swingable in saidplane, an elongated, stiff but flexible and resilient support structuregenerally paralleling said plane and positioned with its opposite endsoverlapping the adjacent ends of said trusses, first support meanssupporting the opposite ends of said resilient support structure fromremote portions of said trusses spaced therealong from the adjacent endsof said trusses and with said opposite ends generally paralleling thecorresponding truss portions and supported therefrom for limitedlengthwise guided shifting longitudinally therealong, second supportmeans connected to and supported at least in part from said trusses andsupportingly engaged with predetermined portions of said resilientsupport structure disposed at a plurality of points spaced aparttherealong between and from said opposite ends and operative, inresponse to relative angular displacement of said trusses, to supportand automatically shifT said spaced predetermined portions of saidsupport structure to predetermined positions along a substantiallyconstant radius path containing the opposite ends of said supportstructure during angular displacement of said movable truss relative tosaid stationary truss, and conveyor belt support means supported fromand closely spaced along said resilient support structure and the remoteend portions of said trusses on the remote sides of said first supportmeans for supporting a flexible conveyor belt in a path substantiallyparalleling the remote end portions of said trusses and said resilientsupport structure in order that the path of that portion of thesupported conveyor belt extending between said remote end portions ofsaid trusses will comprise a substantially constant radius arc whoseopposite ends merge smoothly into the portions of the conveyor beltsupported from said remote end portions.
 2. The combination of claim 1wherein said trusses each include opposite side longitudinal members,said resilient structure including a pair of spaced side-by-sideelongated, stiff but flexible and resilient members, said resilientmembers each being positioned with their opposite ends overlapping theadjacent ends of one pair of corresponding side longitudinal members andsupported therefrom by said first support means.
 3. The combination ofclaim 2 wherein said elongated support structure includes rigidtransverse support members extending between and rigidly interconnectingcorresponding portions of said resilient members defining saidpredetermined portions of said resilient support structure.
 4. Thecombination of claim 3 wherein each of said resilient members comprisesa pair of elongated spaced and parallel resilient structural membersrigidly interconnected at a plurality of points spaced therealong. 5.The combination of claim 3 wherein said conveyor belt support meansincludes a plurality of belt craddling structures extending between andrigidly connected to said resilient members at points spaced therealong.6. The combination of claim 1 wherein said trusses each include oppositeside longitudinal members, said resilient support structure including apair of spaced side-by-side elongated, stiff but flexible and resilientmembers, said resilient members each being positioned with theiropposite ends overlapping the adjacent ends of one pair of correspondingside longitudinal members and supported therefrom by said first supportmeans, said first support means comprising a sleeve member supportedfrom and extending along each opposite side longitudinal member, theopposite ends of said resilient members being slidingly telescoped in acorresponding sleeve member.
 7. The combination of claim 1 including anupstanding support tower, said first end of said stationary truss beingsupported from an upper portion of said support tower, said upperportion of said support tower comprising said mounting means for saidone end of said movable truss.
 8. The combination of claim 7 includingmeans connected between said tower and the other end of said movabletruss for supporting the latter in adjusted angularly displacedpositions relative to said stationary truss.
 9. The combination of claim1 including a stationary base, said stationary truss being inclined withsaid first end thereof uppermost, means supporting the second end ofsaid stationary truss from said base for angular displacement about anupstanding axis, the lower end of said tower including a mobile supportunit adapted to move in an arcuate path disposed in a plane normal tosaid upstanding axis and having the latter as its center of curvature.